Foster will play a love interest for Amber (Mae Whitman) for a multi-episode arc. The pair will meet when Amber gets a job at her aunt's law firm, where he works as a valet.
The 25-year-old actor will first appear in late April. In the meantime, the series finale of Greek is slated to air Monday, March 7 at 9/8c on ABC Family.
Parenthood airs Tuesdays at 10/9c on NBC.